able to be increased from to , but this involved lowering the top speed from to . As a special feature, the locomotive had been fitted with a two axle subframe supporting the brake frame for the electromagnetic rail brakes, which were supplied with current through the overhead catenary. Due to these subframes, the locomotive's wheel arrangement is correctly described as C′2′C′ in its original form, and B′2′B′ in its modified form. The two axle subframe, together with a small luggage compartment, has never been taken into account in the official classification of the locomotive. Strictly speaking, the locomotive should be classified as GDe 4/6 in its present configuration. Later operations In 1943, the previously independent Bernina Railway was taken over by the Rhaetian Railway (RhB), which is the main railway network in the Canton of Graubünden, Switzerland. At the time of the takeover, the locomotive was renumbered 181. It continued to haul trains on the Bernina Railway until its withdrawal from service in 1970. In the same year, the locomotive was transferred to the Blonay-Chamby Railway, where it was initially used on a regular basis. As a result of damage to its electrical equipment in 1990, it was taken out of the Blonay-Chamby's operational fleet. Only in 2008, thanks to a generous sponsor, was it worked up sufficiently to be able to re-enter active service. Sources, further reading This article is based upon a translation of the German language version as of May 2010. Literature SLM locomotives Brown, Boveri & Cie locomotives Rhaetian Railway locomotives C′C′ locomotives B′B′ locomotives Electric locomotives of Switzerland Railway locomotives introduced in 1916 Metre gauge electric locomotives 1000 V DC locomotives